diff --git a/contracts/examples/StandardToken.sol b/contracts/examples/StandardToken.sol
index 4399e9513..c0414c1ca 100644
--- a/contracts/examples/StandardToken.sol
+++ b/contracts/examples/StandardToken.sol
@@ -13,7 +13,7 @@ import "../token/ERC20/ERC20Pausable.sol";
 contract StandardToken is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pausable {
     function initialize(
         string memory name, string memory symbol, uint8 decimals, uint256 initialSupply, address initialHolder, 
-        address[] memory minters, address[] memory pausers
+        address[] memory minters, address[] memory pausers, address sender
     ) public initializer {
         ERC20Detailed.initialize(name, symbol, decimals);
 
@@ -23,11 +23,11 @@ contract StandardToken is Initializable, ERC20Detailed, ERC20Mintable, ERC20Paus
         }
 
         // Initialize the minter and pauser roles, and renounce them
-        ERC20Mintable.initialize(msg.sender);
-        renounceMinter();
+        ERC20Mintable.initialize(sender);
+        _removeMinter(sender);
 
-        ERC20Pausable.initialize(msg.sender);
-        renouncePauser();
+        ERC20Pausable.initialize(sender);
+        _removePauser(sender);
 
         // Add the requested minters and pausers (this can be done after renouncing since
         // these are the internal calls)
diff --git a/contracts/token/ERC20/StandaloneERC20.sol b/contracts/token/ERC20/StandaloneERC20.sol
index abf0b768f..9d5e6cedc 100644
--- a/contracts/token/ERC20/StandaloneERC20.sol
+++ b/contracts/token/ERC20/StandaloneERC20.sol
@@ -13,7 +13,7 @@ import "./ERC20Pausable.sol";
 contract StandaloneERC20 is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pausable {
     function initialize(
         string memory name, string memory symbol, uint8 decimals, uint256 initialSupply, address initialHolder,
-        address[] memory minters, address[] memory pausers
+        address[] memory minters, address[] memory pausers, address sender
     ) public initializer {
         ERC20Detailed.initialize(name, symbol, decimals);
 
@@ -21,11 +21,11 @@ contract StandaloneERC20 is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pa
         _mint(initialHolder, initialSupply);
 
         // Initialize the minter and pauser roles, and renounce them
-        ERC20Mintable.initialize(msg.sender);
-        renounceMinter();
+        ERC20Mintable.initialize(sender);
+        _removeMinter(sender);
 
-        ERC20Pausable.initialize(msg.sender);
-        renouncePauser();
+        ERC20Pausable.initialize(sender);
+        _removePauser(sender);
 
         // Add the requested minters and pausers (this can be done after renouncing since
         // these are the internal calls)
@@ -39,16 +39,16 @@ contract StandaloneERC20 is Initializable, ERC20Detailed, ERC20Mintable, ERC20Pa
     }
 
     function initialize(
-        string memory name, string memory symbol, uint8 decimals, address[] memory minters, address[] memory pausers
+        string memory name, string memory symbol, uint8 decimals, address[] memory minters, address[] memory pausers, address sender
     ) public initializer {
         ERC20Detailed.initialize(name, symbol, decimals);
 
         // Initialize the minter and pauser roles, and renounce them
-        ERC20Mintable.initialize(msg.sender);
-        renounceMinter();
+        ERC20Mintable.initialize(sender);
+        _removeMinter(sender);
 
-        ERC20Pausable.initialize(msg.sender);
-        renouncePauser();
+        ERC20Pausable.initialize(sender);
+        _removePauser(sender);
 
         // Add the requested minters and pausers (this can be done after renouncing since
         // these are the internal calls)
diff --git a/contracts/token/ERC721/StandaloneERC721.sol b/contracts/token/ERC721/StandaloneERC721.sol
index 38b83647b..52c32276e 100644
--- a/contracts/token/ERC721/StandaloneERC721.sol
+++ b/contracts/token/ERC721/StandaloneERC721.sol
@@ -15,17 +15,17 @@ import "./ERC721Pausable.sol";
 contract StandaloneERC721
     is Initializable, ERC721, ERC721Enumerable, ERC721Metadata, ERC721MetadataMintable, ERC721Pausable
 {
-    function initialize(string memory name, string memory symbol, address[] memory minters, address[] memory pausers) public initializer {
+    function initialize(string memory name, string memory symbol, address[] memory minters, address[] memory pausers, address sender) public initializer {
         ERC721.initialize();
         ERC721Enumerable.initialize();
         ERC721Metadata.initialize(name, symbol);
 
         // Initialize the minter and pauser roles, and renounce them
-        ERC721MetadataMintable.initialize(msg.sender);
-        renounceMinter();
+        ERC721MetadataMintable.initialize(sender);
+        _removeMinter(sender);
 
-        ERC721Pausable.initialize(msg.sender);
-        renouncePauser();
+        ERC721Pausable.initialize(sender);
+        _removePauser(sender);
 
         // Add the requested minters and pausers (this can be done after renouncing since
         // these are the internal calls)
diff --git a/test/examples/SimpleToken.test.js b/test/examples/SimpleToken.test.js
index 1ec65ee07..4e89f783b 100644
--- a/test/examples/SimpleToken.test.js
+++ b/test/examples/SimpleToken.test.js
@@ -1,7 +1,7 @@
 const { constants, expectEvent } = require('openzeppelin-test-helpers');
 const { ZERO_ADDRESS } = constants;
 
-const SimpleToken = artifacts.require('SimpleToken');
+const SimpleToken = artifacts.require('SimpleTokenMock');
 
 contract('SimpleToken', function ([_, creator]) {
   beforeEach(async function () {
diff --git a/test/examples/StandardToken.test.js b/test/examples/StandardToken.test.js
index 108821ea5..c4a00bc06 100644
--- a/test/examples/StandardToken.test.js
+++ b/test/examples/StandardToken.test.js
@@ -1,11 +1,7 @@
 const encodeCall = require('zos-lib/lib/helpers/encodeCall').default;
 const { shouldBehaveLikeERC20Mintable } = require('../token/ERC20/behaviors/ERC20Mintable.behavior');
 
-const BigNumber = web3.BigNumber;
-
-require('chai')
-  .use(require('chai-bignumber')(BigNumber))
-  .should();
+const { BN } = require('openzeppelin-test-helpers');
 
 const StandardToken = artifacts.require('StandardToken');
 
@@ -14,9 +10,9 @@ contract('StandardToken', function ([
 ]) {
   const name = 'StdToken';
   const symbol = 'STDT';
-  const decimals = 18;
+  const decimals = new BN('18');
 
-  const initialSupply = 300;
+  const initialSupply = new BN('300');
 
   const minters = [minterA, minterB];
   const pausers = [pauserA, pauserB];
@@ -28,10 +24,9 @@ contract('StandardToken', function ([
   });
 
   async function initialize (token, name, symbol, decimals, initialSupply, initialHolder, minters, pausers, from) {
-    const callData = encodeCall('initialize',
-      ['string', 'string', 'uint8', 'uint256', 'address', 'address[]', 'address[]'],
-      [name, symbol, decimals, initialSupply, initialHolder, minters, pausers]);
-    await token.sendTransaction({ data: callData, from });
+    const signature = 'initialize(string,string,uint8,uint256,address,address[],address[],address)';
+    const arguments = [name, symbol, decimals, initialSupply, initialHolder, minters, pausers, from];
+    await token.methods[signature](...arguments, { from });
   }
 
   context('with all arguments', function () {
@@ -77,8 +72,8 @@ contract('StandardToken', function ([
   });
 
   it('can be created with zero initial balance', async function () {
-    await initialize(this.token, name, symbol, decimals, 0, ZERO_ADDRESS, minters, pausers, deployer);
-    (await this.token.balanceOf(initialHolder)).should.be.bignumber.equal(0);
+    await initialize(this.token, name, symbol, decimals, new BN(0), ZERO_ADDRESS, minters, pausers, deployer);
+    (await this.token.balanceOf(initialHolder)).should.be.bignumber.equal('0');
   });
 
   it('can be created with no minters', async function () {
diff --git a/test/token/ERC20/StandaloneERC20.test.js b/test/token/ERC20/StandaloneERC20.test.js
index aedd61c25..0e29ec52e 100644
--- a/test/token/ERC20/StandaloneERC20.test.js
+++ b/test/token/ERC20/StandaloneERC20.test.js
@@ -1,12 +1,7 @@
 const encodeCall = require('zos-lib/lib/helpers/encodeCall').default;
 const { shouldBehaveLikeERC20Mintable } = require('./behaviors/ERC20Mintable.behavior');
-const shouldFail = require('../../helpers/shouldFail');
 
-const BigNumber = web3.BigNumber;
-
-require('chai')
-  .use(require('chai-bignumber')(BigNumber))
-  .should();
+const { shouldFail, BN } = require('openzeppelin-test-helpers');
 
 const StandaloneERC20 = artifacts.require('StandaloneERC20');
 
@@ -15,9 +10,9 @@ contract('StandaloneERC20', function ([
 ]) {
   const name = 'StandaloneERC20';
   const symbol = 'SAERC20';
-  const decimals = 18;
+  const decimals = new BN(18);
 
-  const initialSupply = 300;
+  const initialSupply = new BN(300);
 
   const minters = [minterA, minterB];
   const pausers = [pauserA, pauserB];
@@ -29,17 +24,15 @@ contract('StandaloneERC20', function ([
   });
 
   async function initializeFull (token, name, symbol, decimals, initialSupply, initialHolder, minters, pausers, from) {
-    const callData = encodeCall('initialize',
-      ['string', 'string', 'uint8', 'uint256', 'address', 'address[]', 'address[]'],
-      [name, symbol, decimals, initialSupply, initialHolder, minters, pausers]);
-    await token.sendTransaction({ data: callData, from });
+    const signature = 'initialize(string,string,uint8,uint256,address,address[],address[],address)';
+    const arguments = [name, symbol, decimals, initialSupply, initialHolder, minters, pausers, from];
+    await token.methods[signature](...arguments, { from });
   }
 
   async function initializePartial (token, name, symbol, decimals, minters, pausers, from) {
-    const callData = encodeCall('initialize',
-      ['string', 'string', 'uint8', 'address[]', 'address[]'],
-      [name, symbol, decimals, minters, pausers]);
-    await token.sendTransaction({ data: callData, from });
+    const signature = 'initialize(string,string,uint8,address[],address[],address)';
+    const arguments = [name, symbol, decimals, minters, pausers, from];
+    await token.methods[signature](...arguments, { from });
   }
 
   describe('with all arguments', function () {
diff --git a/test/token/ERC721/StandaloneERC721.test.js b/test/token/ERC721/StandaloneERC721.test.js
index ce301046d..7fb022212 100644
--- a/test/token/ERC721/StandaloneERC721.test.js
+++ b/test/token/ERC721/StandaloneERC721.test.js
@@ -1,10 +1,6 @@
 const encodeCall = require('zos-lib/lib/helpers/encodeCall').default;
 
-const BigNumber = web3.BigNumber;
-
-require('chai')
-  .use(require('chai-bignumber')(BigNumber))
-  .should();
+require('openzeppelin-test-helpers');
 
 const StandaloneERC721 = artifacts.require('StandaloneERC721');
 
@@ -20,10 +16,9 @@ contract('StandaloneERC721', function ([_, deployer, minterA, minterB, pauserA,
   });
 
   async function initialize (token, name, symbol, minters, pausers, from) {
-    const callData = encodeCall('initialize',
-      ['string', 'string', 'address[]', 'address[]'],
-      [name, symbol, minters, pausers]);
-    await token.sendTransaction({ data: callData, from });
+    const signature = 'initialize(string,string,address[],address[],address)';
+    const arguments = [name, symbol, minters, pausers, from];
+    await token.methods[signature](...arguments, { from });
   }
 
   it('can be created with no minters', async function () {